Archived

Avalanche Forecast

Dec 17th, 2011–Dec 18th, 2011

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Kootenay Boundary.

Confidence

Fair - Intensity of incoming weather is uncertain

Weather Forecast

Sunday: light snowfall with 3-5 cm expected. Alpine temperatures dropping to around -9?C. Moderate northwesterly winds.Monday: Mostly dry. Alpine temperatures around -8?C. Moderate westerly winds.Tuesday: Light snowfall. Alpine temperatures around -4?C. Strong westerly winds.

Avalanche Summary

There have been no recent reports of avalanches from this area.

Snowpack Summary

10-15 cm low density snow sits above a weak layer of well developed surface hoar. At present, the snow above this weak layer is not sufficiently deep and has not yet consolidated into a cohesive slab to set up the structure required for slab avalanches. Bear in mind, however, as more snow is added to the snowpack and the processes of settlement the uppre snowpack, the more likely slab avalanches become. We typically see dangerous slab avalanches start to occur when the depth to the weak layer reaches approximately 40 cm. Below the surface issues, the mid pack is strong. The basal snowpack layers are faceted. However, we have not had reports of instabilities affecting the lower layers in this area.

Avalanche Problems

Wind Slabs

Moderate to strong south west winds have set up localized wind slabs on north through east aspects along ridgelines. Note winds are forecast to shift to the northwest. Watch for new loading on southeast aspects.

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2